Angular cutting tool



Sept. 14, 1954 B A SWANSON 2,688,797

ANGULAR CUTTING TOOL Filed Feb. 27, 1952 Patented Sept. 14, 1954 UNITED STATES NT OFFICE '7 Claims.

This invention is directed to improvements in cutting toolsfand more particularly to a toolhaving a reciprocable cutter operating in association with a ixed cutter jaw, suchas-is illustrated and claimed in my application Serial No. 273,589 :filed February 27, 19512 for an improved cutting tool.

The invention herein set forth is characterized by providing a separate moving coupling element between the end of the` reciprocating piston on the one side of said coupling element and the adjacent end of thefshanlr ofthe cutter tool on the other side, thelongitudinal aXis of reciprocation of said piston beingdisposed at an angle to the longitudinal axis of said shan-l; of said cutting tool.

A principal object of the present invention is to provide a novel driving `coupling between a reciprocable piston hammer and a reciprocable cutter whereby a rapid hammeraction may be applied tothe cutter by the piston actuated-hammer through angularly related paths.

More specifically the invention of the present application has for an object to provide a novel coupling between a reciprocating hammer member moving inone-path and a reciprooable `cutter moving in a path disposed at an angle to the path of movement of the hammer, whereby the hammer and the cutter are free to move independently one of the other and atthe same time the desired driving movement is imparted from the hammer to the cutter around abend orI angle with perfect freedom, whereby the parts can move at high speed for the performance of the cutting operation,

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming a part of the specification, with the understanding, however, that the invention is not to be limited to the exact details of construction shown and described since obvious modifications will occur to a person skilled in the art.

In the drawings:

Figure 1 is a view in top plan of a tool constructed in accordance with the present invention, showing one angle betweenthe reciprocating cutter and the reciprocating hammer member.

Figure 2 is a longitudinal section takensubstantially on the line l2---2 of Figure 1.

Figure 3 is a view of the cutter head, against one part of which a piece'of work bears in the use ofthe tool.

Figure 4- is a transverse section taken substantially on the line 2 4 of Figure 2.

Figure 5 is a longitudinal section through the forward end of the tool handle and piston cylinder and a cutter head showing the disposition of the hammer and reciprocable cutter for movement along perpendicularly related paths.

Figure 6 is av view in transverse section through the valve end of; a .modified construction showing the compressed air exhaust passages opening rearwardly.

Figure '7 is a sectional view taken on line 'i4-l of Figure 2.

Referring now more particularly to the drawings, the numeral I generally designates the `handle of the tool which, as shown, is in the form of an Yelongated body of circular cross section and having formed therein from one end the cylindrical chamber l2.

Formed in and in a direction transversely of the rear end portion I4 of the body, is the valve spring chamber I6, the outer end of which is closed by the threaded plug i8, while the inner end of the chamber is of reduced diameter as at Ilia, forming an annular valve seat 2d upon which positions the valve ball 22, which is in the larger end of the air chamber IS as shown. Interposed between the ball 22 and the plug Iii isa spring 24 which maintains the ball positioned on the seat 20.

Extending into the body portion lil at the opposite end of the chamber I6 from thevplug I8, is the valve ball control button E5, by means of which the ball can be shifted kfrom its seat to permit air under pressure to pass from the air inlet passage 26 to the longitudinally extending passage 2l, which is formed in the wall of the cylinder and opens into the circumferential air admission channel 28 yformed-in the inner wall of the cylinder l2 as shown.

At opposite sides of the channel 28 and spaced a predetermined distance therefrom are the two circumferential channels 29 which are formed in the wall of the cylinder l2 andeach of these channels connects with an air exhaust bore or passage 30 which is formed in the body of the handle and in the form of the tool illustrated in Figure 2, extend forwardly and open through the forward end of the handle.

Within the cylinder i2 is theair operated piston which is generally designated 3|. This piston carries on its forward end the hammer pin 32 which extends through the bushingcollar 33 which is'fltted into the forward end of the cylinder-in the manner shownv and which has an enthe illustration and description of my air operated engine forming the subject matter of my co-pending application for patent Serial No. 259,051 led November 30, 1951, and since the specific construction of the piston and its operation are not the subject matter for patent under the present application it is not believed necessary to give a detailed explanation of the construction and operation of the piston, other than to State broadly that the admission of air under pressure through the passage 21 causes the piston to be reciprocated at high speed by reason of the air passing rst into one end of the cylinder l2 and then into the opposite end, the air previously introduced and remaining in the end of the cylinder toward which the piston is moving being caused to escape through one of the piston passages 3Ia to the atmosphere by way of one of the barrel wall passages 3l). In the initial introduction of air through the passage 21 the air may enter one end of the cylinder by way of one of the passages 3 la either by initially passing into such passage through the central starting port 3lb or through a port 3io opening radially of the piston into a wide circumferential channel 33, which port 3 lc is connected with one of the axial passages 3|a to carry the introduced air to one end of the piston cylinder. As the piston moves away from the end of the cylinder into which the air is introduced through one of the passages 3|a the air in the opposite end of the cylinder will escape through another one of the passages 3| a which opens through the advancing end of the piston and leads to the port 3lc opening into the other circumferential piston channel 33.

The forward end of the barrel handle has detachably secured thereto a cutter head which is generally designated 35 and which comprises a plate portion, generally designated 36 and a shank portion, generally designated 31.

The shank portion and plate portion together form the entire head 35 as stated but the shank is longitudinally divided and one of the two sections, designated 38, is in one piece with the v plate 36 and is secured to the other head section by the transverse screws 38.

The shan'k of the cutter head, in the form shown in Figures 1 to 3, has an obliquely angled rear end terminus 40 which joins a mounting or attaching flange 4I which fits against the flange 34 of the bushing 33. This flange 4|, with the flange 34, is bolted to the end of the handle barrel by bolts or screws 42.

Extending longitudinally through the shank portion 31 of the cutter head unit and through the angled terminus 40 is the passage 43. As shown in Figure 2 the rear end of this passage 43 aligns with the passage 33a of the bushing 33 and the forward end of the hammer pin 32 of the piston enters the rear end of the passage 43 as shown.

Within the forward end portion of the passage 43 is slidably mounted the cutter 44 and interposed between the rear end of the cutter and the forward end of the hammer pin 32 in the bend 43a of the passage is a free moving ball 45. This ball moves freely in a short arcuate path around the bend, between the spaced ends of the cutter and piston pin and when the piston pin is moved 4 forwardly it will contact the ball 45 and move the ball a short distance in the bend 43a of the passage 43, forcing it against the obliquely angled back end 44a of the cutter 44 and thus driving the cutter forwardly.

The passage 43, inwardly of the forward end, is widened to form the rearwardly facing shoulder 4412, and the cutter has a portion of its rear end widened to position in the widened part of the passage and to form a forwardly facing shoulder 43D which opposes the shoulder 44h and between these opposed shoulders is a coil spring 44 which urges the cutter rearwardly to retracted position.

The cutter head plate 44e has been fully illustrated and described in my co-pending application filed of even date herewith, and accordingly it is not believed that a detailed description of its construction is here necessary other than to set forth that the plate has formed therein from and through its periphery the work receiving slot 46 which divides the plate into a fixed jaw portion 41 and a rest portion 48.

The portions 41 and 48 are disposed in angularly related planes whereby the outer end or point of the jaw portion 41 is inclined away from the shank while the portion 48 has an opposite inclination. Thus in the use of the tool for the cutting of a sheet of metal or other sheet material, an edge of the sheet is introduced into the slot 46 with the xed jaw portion 41 lying beneath the sheet and the portion 48 lying above and resting upon the top of the sheet. The cutter 44 has the inclined cutting edge 44h which moves across and in shearing relation with the longitudinal edge or corner 41a of the jaw 41 and these cutting edges are disposed at angles which intersect so as to thereby cooperate to have a shearing action on the sheet.

In the form of the invention illustrated in Figure 5, the barrel handle 1s generally designated Illa and in this construction the air admission passage 21a and the exhaust passages 30a are shown extending to the rear end of the barrel handle, the exhaust passages 30a opening through the rear end of the barrel while the air admission passage opens into the radial air chamber I 6a. The other parts of the air admission mechanism are the same as shown in Figure 2 and accordingly a detailed description of the same is not believed to be necessary.

In the form illustrated in Figure 5 the cutter head which is generally designated 35a has the shank 31a provided with the right angularly extending terminal portion 40a. Thus the passage 43D at its rear end has the right angled turn 43e. In this right angle or turn are located the two freely moving power transmitting balls 45a, one of which is contacted by the hammer stem 32a of the piston 3| :c while the other ball contacts the rear end of the cutter 44. By this arrangement it will be readily seen that when the piston hammer stem 32a moves forwardly it will drive the adjacent ball 45a against the next ball and the two balls will thus transmit reciprocable movement around the right angle bend to the cutter 44' so as to impart forward movement to the cutter in the desired manner.

From the foregoing it will be readily seen that there is provided by the present invention a novel means whereby reciprocable movement between two parts can be readily transmitted around bends so that such parts can be reciprocated at high speed with a minimum of friction.

I claim:

1. In a cutting tool, a chambered handle body, a reciprocable fluid driven piston therein, the chamber of the body having an axial opening at one end, a hammer reciprocable in and having an end extending through said opening and operatively coupled with the piston to be reciprocated thereby, means for introducing power fluid into and exhausting it from the chamber to actuate the piston, a cutting tool head carried by the said one end of the body and including an elongate shank having a passage lengthwise therethrough, the shank being secured at one end to the said one end of the body with the passage and said opening communicating, an elongate cutting member reciprocably supported in said shank passage and having a cutting end projecting through the other end of the shank passage, and means forming a free angular moving coupling in the shank passage between the said extended end of the hammer and the adjacent end of the cutting member.

2. The invention according to claim 1, wherein said free moving coupling comprises a ball lying in the passage.

3. The invention according to claim 1, wherein said shank has a bend therein to direct the cutting member in a line at an angle to the line of reciprocation of the hammer, and said free moving coupling comprising a ball lying in the passage in the bend and separating the angularly opposed ends of the hammer and cutting member.

4. The invention according to claim 1, wherein the wall of the shank passage and a part of the cutting member lying in said passage have spaced opposing shoulders, and a compression spring interposed between said shoulders, said shoulders being so positioned relative to the cutting end of the cutter as to compress the spring upon the forcing of the cutting forwardly.

5. A cutting tool comprising a body having a piston chamber, a piston positioned for reciproeating movement in said chamber, the chamber having an opening leading from one end,I a hammer element lying in said opening and adapted to have driving movement imparted thereto by the piston, means for effecting reciprocal movement of the piston in the cylinder, a tool head coupled to the body at the opening end of the chamber, a tool supported by the head for limited working movement, the tool having a portion at the end of said opening remote from the hammer positioned to receive operating power from the hammer, and a free moving coupling interposed between said tool portion and said hammer to receive and transfer driving blows from the hammer to said tool portion for the working movement of the tool.

6. A cutting tool according to claim 5, wherein said tool head is provided with a passage leading to said cylinder opening, the said tool portion being slidably positioned in said passage and having an end engaged by said free moving coupling, and a spring element interposed between a part of the head and a part of said tool portion and constantly urging retraction of the tool.

7. A cutting tool according to claim 5, wherein said tool head has a passage disposed at right angles to the axis of the piston chamber and forming a right angle bend with said chamber opening, the said tool portion being slidably movable in said passage, and said free moving coupling comprising two balls in contacting relation in said angle, one of the balls being positioned with its center in the axis line of the piston chamber and the other ball being positioned with its center in the longitudinal center of the passage.

References Cited in the file of this patent UNITED STATES PATENTS Number 

